Abstract
How does the brain work? What is “the neural code”? How is the elegant structure of the brain used, is it an information processing machine? The complexity of the brain suggests that neuroscience offers rich opportunities for systems approaches. However, there is little interaction between systems biology and neuroscience, creating a need and opportunity to relate observed complexity to emergence of robust function.

I hope to provoke discussion of these issues using the specific example of the brain’s regulation of physiological homeostasis, in which there is a surprising disconnect between the robust, linear input-output regulatory behavior and highly conditional central neuronal measures, across all scales from genetic to neural circuit.

Brain data shows complexity and heterogeneous variability. It seems that robust controlled-system responses ride on top of variable and dynamic underlying mechanisms, suggesting that the interactions of the components provide robust control and that system responses are not particularly sensitive to the variability of any one component (or possibly many components).